The use of base isolation systems through the uplift of the existing monumental and historical masonry buildings

The present paper assesses the uplift of existing monumental and historical masonry buildings where base isolation systems are installed as a retrofitting measure. Two reinforced concrete (RC) foundation mats are created at the base of the existing structure to uplift the sample buildings. Hydraulic jacks are located along the bearing walls and tend to be as less intrusive as possible. Such jacks are controlled automatically through an ad-hoc algorithm aimed at minimizing the overstress of the superstructure and preventing significant differential settlements. The overstress and differential settlements are limited by uplifting, with an iterative procedure, the RC foundation mat that is rigidly connected to the superstructure. Modelling of the uplift of the foundation mat and the superstructure is a challenging task. Two case study are investigated in the present work: a traditional masonry residential building and a typical Christian church located in the South of Italy. Refined yet versatile finite element (FE) models of the sample structures have been implemented and are used to determine the stress/strain distributions within the superstructure. The FE models were calibrated on the basis of in-situ measurements for both structures. The calibrated numerical models were then utilized to perform parametric analyses